You are kinda right, but like superhoody said, it's not fenrir. The wolfguts that loki is tied up with, is one of his other sons that was transformed into a wolf together with his brother, and it was the brother that killed the wolf that he is tied up with. And now the other brother roams jörmungard, because of what he did. So yes, Norse Mythologi is crazy, but cool.

Actually, before Loki got a thing for the crazy magic lady. He had two sons. Normal sons mind you. But eh, Loki went down with the crazy magic lady. After som Frost Giant on Crazy Magic God Woman action, the results were Fenrir, Sleipnir, Jormugand and Hel, the Half Frost Giant, Half God, who were bannished because she was the daughter of the crazy magic god woman. So she was cast into Niflhel.
As punishment for having several children with the magic crazy lady, his two sons were cursed. One of his sons was turned into a wolf, his other son was dismembered and after Loki himself was cast into Niflheim, his sons guts surrounded hit, then turned to iron, chaining Loki to the floor, until the time of Ragnarok.

Norse mythology sounds ******* awesome. I know there are a lot of split stories to read, just like with Greek mythology, but would there happen to be any single, coherent text that legit covers Ragnarok and events related to it? That'd be a novel I could seriously get into.

I don't know about a book that would be in the perspective of a god during Ragnarok, but right here describes the events that go on pretty well
You need to login to view this link
This site is the best I've found so far for Norse Mythology.